The company has used Borkowski for the past two years, but is now reviewing its PR support.
The review is entering the final stages, with the firm having drawn up a shortlist of four, and pitches expected to take place in the next couple of weeks. The pitch process is being managed by Creative Brief.
Freesat is a joint venture between the BBC and ITV and has provided free HD digital TV across the UK since spring 2008, offering more than 200 TV and radio channels.
The review coincides with the arrival of greater competition in the HD market. Freeview launched its HD service at the end of April, while Sky News in HD also launched during the general election.
The chosen agency will have to help the company redefine its positioning following these changes, as well as helping to increase understanding of the product in a cluttered market.
Freesat marketing and communications director Will Abbott insisted that changes in the market were not the only reason for the review.
He said: 'We felt it was the right time for us to review our ongoing consumer PR.
'We are not reviewing because Sky and Freeview offer HD TV. But we will be ensuring we make it as simple as possible to understand our service.'
Freesat launched in 2008, with tech specialist Firefly handling PR for a six-month pre-launch period.
Borkowski was then hired in May 2008 to oversee the campaign targeting trade, specialist and online media.
Freesat is delivered via satellite, making it available to households who cannot access digital terrestrial TV.
TV services throughout the UK will go completely digital by 2012.